Apparatus for maneuvering on a submerged surface

ABSTRACT

A remotely controlled submerged electro-hydraulic cleaning system for removing growths from a ship&#39;&#39;s hull is disclosed. The system basically comprises four sections including a cleaning unit, a control console and a power supply unit. The cleaning unit includes a device having rotating scrubbing brushes and reduced pressure holds the device against the ship while it is being driven along the submerged surface of the hull.

United States Patent Winn Sept. 23, 1975 APPARATUS FOR MANEUVERING ON A SUBMERGED SURFACE [56] References Cited [75] lnventor: Russell Edward Winn, Kilbrittain UNITED STATES PATENTS Castle l' 3,337,889 8/1967 West 15/11 [73] Assgneei fif ig f g & Engmeer'ng FOREIGN PATENTS OR APPLICATIONS 1,038,209 8/1966 United Kingdom 15/312 R [22] Filed: July 12, 1973 [21] A No 378,660 Primary Examiner-Edward L. Roberts An ,A I, F F.D ldP' Related US. Application Data v omey 88" or "m Ona ans [63] Continuation of Ser. No, 65,449, Aug. 20, 1970,

abandoned, which is a continuation-in-part of Ser. [57] ABSTRACT 7 21 13, 19681 abandoned, which is a A remotely controlled submerged electro-hydraulic contmuation-m-part of Ser. No. 531,459, March 3, cleaning System for removing growths from a Ships 1966 abandoned hull is disclosed. The system basically comprises four sections including a cleaning unit, a control console [30] Fore'gn Application Pnonty Data and a power supply unit. The cleaning unit includes a Mar. 4, United device having rotating crubbing brushes and reduced pressure holds the device against the ship while it is [1.8. CI- being driven along the ubmerged urface f the [51] Int. Cl. B63B 59/02 [58] Field Of Search 15/1.7, 312 R; 114/222 7 Claims, 18 Drawing Flgures US Patent Sept. 23,1975 Sheet 1 of7 3,906,572

DISTRIBUTOR GENERATOR cousous' US mm Sept. 23,1975 Sheet 2 of 7 3,6572

US Patent Sept. 23,1975 Sheet 3 of7 3,906,572

US Patent Se t. 23,1975 Sheet40f7 3,906,572

US Patent S ept.23 ,1975 Sheet 7 0f7 3,906,572

27 FIG.9.

FIG. 10.

APPARATUS FOR MANEUVERING ON A SUBMERGED SURFACE CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of application Ser. No. 65,449, filed August 20, 1970, now abandoned, which is a continuation-impart of Ser. No. 752,195, filed Aug. 13, 1968, now abandoned which is a continuation-in-partof Ser. No. 531,459, filed Mar. 3, 1966, now abandoned.

SUMMARY OF THE INVENTION This invention relates broadly to an overall cleaning system including an apparatus which can be maneuvered on a submerged surface and more particularly,to an apparatus that can be used for cleaning the hull of a ship while it is in the water, or for cleaning the inside of tanks, or it can be used as an underwater survey platform.

Basically, the cleaning system comprises four sections including a cleaning unit, a control console and a generator power supply unit. Additionally, there may be provided a distributor box or reel unit for feeding out the interconnecting power cable.

The cleaning unit has four direction facilities, namely, forward, reverse, left and right (port and starboard). The speed is adjustable and the unit is held to the surface to be cleaned by pressure means, such as a hydraulic impeller. The unit travels along the submerged surface, preferably by means of three hydraulically driven wheels disposed in a triangular configuration, two wheels being located at one end (the rear) transversely disposed on opposite sides of the units longitudinal centerline and one being situated along the centerline at the front. Cleaning is effected by means of three rotary brushes. The power for the cleaning unit is provided by means of a conventional power supply, such as a three-phase electric motor which may then supply power to the impeller. A conventional motor may be provided for the driven wheels and brushes.

The cleaning unit of this invention includes a substantially hollow main body or chamber having an open bottom, a pressure-reducing device capable of continuously maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber; a steerable wheel mounted so that the unit can be driven along a submerged surface (e.g. the hull ofa ship) with the open or bottom side of the chamber being held disposed adjacent the surface to be cleaned; a motor for driving the unit along the submerged surface; and a steering device for controlling directional movement of the steerable wheel and thus the unit, typically the chamber, may be box-like in shape or it may comprise a shape substantially like that of the segment of a sphere with the open bottom formed in the flat edge. The chamber also may have a suitable outlet, which can be a cylindrical tube suitably attached to or inte-.

grally formed with the top wall of the chamber opposite the open side or bottom of the chamber, thereby providing a pressure reduction opening.

The pressure reducing device may comprise a suction pump, eg an. axial piston hydraulic pump, arranged in suitable fashion so that liquid is removed from the interior of the chamber as further enters the chamber about the periphery of the open side. Alternatively, this device may comprisea pump-driven impeller with the impeller blades being conveniently located within the pressure reduction outlet, or a centrifugal pump. Other suitable pressure reducing devices aresatisfactory so long as there is a resultant reduction in the internal pressure of the chamber in the face of liquid entering the chamber, such that the external hydraulic pressure forces the chamber securely into contact with the submerged surface. Thus, the inside of the chamber may be continuously vented to maintain the internal pressure below that acting on the external surface of the chamber. I

The steerable wheel (by which term it is intended to include any other rotatably mounted circular member capable driving the apparatus, e.g., a roller or drum) preferably is mounted within the chamber so that the peripheral running or contact surface thereof projects through the open side of the chamber such that the chamber is supported a small distance, e.g. 5 to 10 cm., from the submerged surface. This wheel may be arranged for operation in a generally conventional manner such as disclosed in US. Pat. Nos. 2,492,649 and 3,035,793. In this way small irregularities or slight curvatures of the surface will not interfere with the maneuverability of the unit. If desired, however, this wheel conveniently could be mounted outside the chamber. In order to facilitate the maneuverability of the unit, it is preferable, if in addition to the steerable wheel, there are two or more supporting wheels, which may be idle or driven in conventional fashion by the drive motor. These wheels are also preferably mounted within the chamber similar to the steerable wheel. In this manner the unit can readily be driven along a submerged surface which is substantially flat over any area at least equal to that of the open side of the chamber. All of the wheels, including the steerable wheel, may be made of suitable rubber or have a rubber tread or tire. Instead of rubber, polyurethane foam, for example, may be used.

The steerable wheel should preferably be mounted so that it is free to swivel through a wide angle, i.e. at least In practice this angle ,will often be greater, e.g. between and or even 360. Preferably, the wheel is free to swivel equally on either side of the neutral position, which results in the apparatus being steered in a straight line. With this wide angle of swivel, the steerable wheel can steer the device very easily and the device can be maneuvered over any part of the submerged surface.

The unit is provided with a motor so that it can be driven along the submerged surface. This motor may be arranged so as to drive the steerable wheel, or, where other wheels are provided, one or more of these wheels may be driven. Thus, the motor may drive a hydraulic pump which pumps hydraulic fluid through a hydraulic motor for driving the steerable wheel and, if desired, the other wheels. Although, according to the preferred embodiment of this invention, there is disclosed hydraulic motors, it is within the scope of the invention to employ electric motors.

There also is provided a steering device for steering the steerable wheel, and this device may comprise a hydraulic motor remotely controlled from the land or a ship, by a hydraulically operated actuator. Means would also be provided to control the flow to the actuator in such a manner as to enable the operator to effect the necessary fine degree of remote steering control. Alternatively, the steering may be carried out by means of hydraulically-operated steering rams operating on the drive wheel through a chain drive and provided with suitable valve devices to maintain tautness in the chain, or alternatively, through a crank or cross-head mechanism. As another alternative the steering may be carried out by an electric motor or other power source which may be remotely controlled and with any necessary mechanical gearing or other mechanism.

Either or both the motor and steering devices are preferably mounted in the chamber in a water-tight compartment, which may contain air or another suitable gas, oil or other suitable liquid. Alternatively, they may be of such a design that they are suitable for oper ating in submerged conditions. If certain control items cannot by the nature of their design operate in submerged conditions, it is preferable that the walls of the water-tight compartment be so formed as to provide integral channels for directing the hydraulic operating fluid to the proximity of the units requiring to be controlled and/or driven.

When the apparatus is used for cleaning a submerged surface, there should be one or more cleaning devices, e.g. rotatable brushes. These brushes project beyond the open bottom of the chamber and are urged into cleaning contact with the submerged surface. The cleaning devices may be conventionally driven and operated in any one of a variety of ways including a separate motor, or the motor of the suction or pressure re ducing device, or by the driving motor, or the hydraulic fluid pumped from the hydraulic pump.

The unit may also have a sensing device and/or instruments for sending back information to the surface, e.g. a gravity-controlled potentiometer, for providing information on the orientation of the unit, or a pressure gauge for relaying information on the hydrostatic pressure.

The unit may also have a television camera for navigation and survey purposes mounted on the chamber.

All the cables for supplying current to the electrical equipment in the unit may pass through a gland in the wall of the chamber. These electrical cables also may act as hoists for lowering and raising the unit into and out of the water, or if desired, there may be provided separate cables for this purpose.

The unit is particularly suited for cleaning the hull of a ship, or for use as a platform for attachment to the hull of a ship for purpose of conducting an underwater survey, or as a stable platform for carrying out mechanical operations underwater.

One method of operating the apparatus of the invention comprises allowing the apparatus to enter the water near the hull ofa ship to a suitable depth, activating the pressure reducing device whereby the chamber attaches itself to the hull, and operating the driving motor whereby the apparatus moves over the surface of the hull. If it is desired to clean the sides of the ship, the cleaning device is activated when the chamber has attached itself to the hull. To remove the apparatus from the water, the pressure reducing device is deactivated, and the unit is recovered, e.g., by allowing it to float to the water surface, or by raising it by means of cables attached thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic side elevation of the cleaning apparatus or unit;

FIG. 1A shows schematically the general layout of the overall cleaning system;

FIG. 2 shows a plan view taken substantially along the line IIII of FIG. 1; and

FIG. 3 shows in schematic representation a perspective view of the apparatus with some of the internal parts of the apparatus being shown in dotted lines; a

FIG. 4 shows a view of the underside of an alternate embodiment of the cleaning apparatus;

FIG. 5 shows a top view of the cleaning apparatus of FIG. 4;

FIG. 6 shows a side view of the cleaning apparatus taken substantially along the line VI-VI of FIG. 4;

FIG. 6A shows details of the mounting of the steerable wheel of FIGS. 1 and 6;

FIG. 7 shows the steering device for the steerable wheel;

FIG. 8 shows a diagram of the hydraulic system and FIGS. 8a through 9 schematically illustrate the operation of the valves;

FIG. 9 shows details of the peripheral corrugations of the chamber; and

FIG. 10 shows a plan view of the control console.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, the chamber 1 has an open bottom side 12 and an outlet 2 disposed in the top wall. Inside the chamber there is provided a watertight casing 10 a driving motor 6, a steering motor 7, a drive motor 8 for the cleaning means (described in detail hereinafter), and a drive motor 16 for the pressure reducing means (also to be described in detail hereinaf ter), all conventionally mounted in the casing 10. These motors also can be conventionally connected to the corresponding parts on the unit.

As shown schematically in the general layout of the overall cleaning system in FIG. 1A, reference also being made to FIGS. 1 to 3 which omit, for clarity of illustration, normal constructional features such as bolts, welds, and linkages, the arrangement of is apparent to those skilled in the art. A power cable 14 is con nected at one end to a distributor reel or alternatively, a distributor box, and at its other end is connected to the generator 64, while the distributor box is connected to the cleaning unit 1 by means of the cable 14'. Also, the distributor is connected by means of a console cable 66 to the control console 63. The power cable 14' shown in FIG. 1A supplies the necessary power via cable 14, which provides power and control signals to the aforementioned motors and passes through a gland 17 on the chamber 1 and a gland 18 in the water-tight casing 10. The actual connection of the cables to the motors and other electrically-operated components is of a-conventional nature,

Attached for rotation externally of the casing 10 are brushes 25 which are conventionally driven by the motor 8. The steerable wheel 4 is conventionally driven by the driving motor 6 and steered by the steering motor 7. This wheel is free to swivel through 360 as indicated in FIG. 2. There are also supporting wheels 3, which are idle and not free to swivel, located at the 0pposite end from the steerable wheel 4. The pump motor 16 drives a propeller or impeller 5, which continuously removes water from inside chamber 1 and discharges it through the outlet 2, thereby lowering the pressure inside the chamber 1 relative to the external hydrostatic pressure. The apparatus is then forced against the submerged surface.

The steering is accomplished by remote control from the control console 63 and may be either manual or automatic. For purposes of this invention, it will suffice to understand that when in the embodiment shown with reference to FIGS. 4 to 8 steerable wheel 4 is steered by means of steering rams 34 and 35, whereas in FIGS. 1 to 3 the steering is obtained by means of the motor 7, when the designated steering control at the console is selected for movement of the chamber in the desired direction. Depending on the particular polarity a conventional electrical circuit produces a predetermined alternating output signal which is fed from the console 63 by means of the console cable 66 and control cable 14' to either a port or starboard solenoid located in a control box 70 on the cleaning unit. A steering valve, which operably is connected with the solenoids, will then operate to provide hydraulic pressure to the required side of a steering ram, thus moving the steering wheel angle to change direction so that the cleaning unit will follow the desired course for cleaning.

If it is desired to move the cleaning unit along a staight path for a relatively long distance, automatic steering is desirable and to accomplish this the direction control at the control console is moved to the auto matic position. The automatic system comprises conventional electrical circuitry which causes the unit to follow a predetermined path of travel.

The casing also contains transducers 21, which send back to the surface information regarding the orientation of the apparatus, and the hydrostatic pressures inside and outside the chamber.

Mounted on the top of the chamber 1 there may be a television camera which is directed towards the front of the apparatus for nagivation and survey purposes.

The present invention will now be described in greater detail with reference to FIGS. 4 to 8 of the drawings.

Referring now to these figures, there is illustrated the chamber 1 with the open side 12 and the outlet or pressure reduction duct 2. Around the peripheral edge of the chamber are disposed a series of corrugations 26 which limit the ingress of water into the chamber. The chamber 1 houses the motor 16, which drives the impeller 5 and the watertight hydraulic pump 9', which as shown may extend outside the housing of the cleaning unit. This hydraulic pump 9 pumps hydraulic fluid through conduits shown only schematically in FIG. 8 (so as not to complicate FIGS. 4 to 7) for driving the wheel and brush motors shown schematically at 6 and the steering rams 34, 35. The operation of the valves associated with this hydraulic circuit is shown in FIGS. 8a through 8f. In order to facilitate handling there is provided a handrail 29 (See FIG. 6) attached to the top side of the chamber by rail supports, two of which are shown at 27 and 28. Although FIG. 6 schematically illustrates that the pump 9 is driven from the impeller shaft, this is merely one possible location and is not intended to be limiting as to the exact physical location of the pump within the cleaning unit.

The cleaning brushes a, 25b and 250 (See FIG. 4) are conventionally driven by hydraulic motors 8a, 8b and 8c which comprise the motor 8 schematically shown in FIG. 1. The steerable wheel 4 is driven by the hydraulic motor 6 and the wheels and 3b are driven respectively by the hydraulic motors 30a and 30b. The rotating impeller 5 continuously removes water from inside chamber 1 and discharges it through the outlet or pressure reduction duct 2, thereby lowering the pressure inside the chamber 1 relative to the external hydrostatic pressure and causing the apparatus to be forced against the submerged surface.

As shown in FIG. 6A, the steerable wheel 4 is directionally driven by means of a yoke 31 mounted therewith in conventional fashion and fixed to a sprocket chain driven wheel or gear 32. Housed inside the steering wheel casing 33 are two hydraulically-operated steering rams 34 and 35 having pistons 36 and 37, respectively. A chain 38 connected to the pistons 36 and 37 drives the wheel 32 in the desired direction.

Referring in general to FIG. 28 and for detail to FIGS. 8a through 8f of the drawings, the hydraulic system is now described. Power to the cleaning unit is supplied from the generator 64 via distributor 62 and cable 14 to the motor 16. The generator provides a three-phase power supply for the overall system and housed in the distributor box are thermal overload, main contactor and a current transformer, all of which are conventional both in construction and arrangement. Thus, the current transformer is connected in one phase and forms part of the main motor current measuring circuit. The distributor reel comprises the distributor box and a large takeup reel on which is mounted the coaxial control cable. The distributor reel and the distributor box each are optional and need not necessarily be employed in the overall system.

Basically the hydraulic operation of the cleaning unit is such that as soon as the main drive motor 16 starts, the impeller 5, the pump 9 and the three brushes 25a, 25b, and 250 rotate. The brush motors 8a, 8b, and 8c and the wheel drive motors 6,. 30a and 3012 are connected in series relation with the pump 9. However, the wheel motors will not operate until they have been signalled to do so from the control console. The control of the wheel motors is effected through the use of a conventional 2-solenoid operated valve 43, generally designated 43a for forward end 43b for reverse operation. In addition there is provided a conventional duel direction steering valve generally designated 44, which operates in conjunction with a standard slipring block (not shown), all of which are conventionally mounted in the casing 10 on the cleaning unit. The forward- /reverse movement is obtained by movement of an appropriate electric direction control switch at the control console 63, which energises either the forward or reverse solenoid 4311 or 43b. FIG. 8a shows the valve in its neutral position. Energising either solenoid results in the desired direction of movement of valve spool 43, which in turn causes hydraulic pressure to be applied to the wheel drive motors 6, 30a, 30b through the slipring block in a given direction. Briefly, by way of description and as shown in FIG. 8, when the forward solenoid 43a is energised, the valve spool 42 moves towards 43a, thereby causing fluid entering at port 43c to pass through the valve leaving at port 43d. The hydraulic fluid then passes through motors 6, 30a and 30b in that order, and reenters the valve at port 43e. The hydraulic fluid then passes through the valve and leaves the valve at' poirt 43f, which is connected internally to port 43g and thence passes to brush motors 8a, 8b, and 8c.

If, alternatively, solenoid 43b is energised (see FIG. 80), the spool 42 will move towards 43b thereby causing the hydraulic fluid entering at port 43c to pass through the valve in such a way that it will leave the valve 43 at port 43c. The hydraulic fluid will then pass through the wheel motors b, 30a, 6 and re-enter valve 43 at port 43d. The hydraulic fluid will then pass through the valve 43, leaving it at port 43g and then to brush motors 8a, 8b and 80. Thus, it is seen that the motor 30b, 30a and b operate in reverse directions compared to when solenoid 43a is energised.

When neither solenoid 43a nor 43b are energised, valve spool 42 is returned to its neutral position by springs (not shown). Hydraulic fluid is allowed to enter at port 436 and since spool 42 does not completely cover or block port 430, fluid is allowed to pass on either side of spool 42 and leave the valve 43 at ports 43f and 43g, thereby allowing only the brush motors 8a, 8b and SC to continue to rotate.

The previously mentioned steering valve 44 is identical in function, operation and construction (see FIGS. 8d-8f) to the forward/reverse valve 43 and is operated either through a port solenoid 440 or a starboard solenoid 44b and is connected to control the steering rams 34, so as to alter the angle of the steering wheel 4 connected therewith in a desired manner. The port and starboard solenoids are also selected by an appropriate control at the console 63. The slipring block is suitably constructed in conventional fashion so as to provide the required 'path for the wheel hydraulic circuits. However, valve spool is constructed so as to prevent passage of fluid facing line 49 when in the neutral position (see FIG. 8d) when neither solenoid 44a or 44b are energised. Hydraulic fluid is housed in the reservoir 40 and is serially pumped by pump 9' via the forward- /reverse valve 43 through the hydraulic motor 6 (which drives the steerable wheel 4), the hydraulic motors 30a and 30b (which drive the wheels 3a and 3b) and then via the valve 43 in the previously described manner to the hydraulic motors 8a, 8b and 80 (which drive the brushes 25a, 25b and 250) and back to the reservoir 40 via line 48. The fluid drives the motors 8a, 8b and 8c in one direction only as brushes 25a, 25b and 25c need rotate in one direction only.

As mentioned heretofore the forward/reverse solenoid 43 is actuated from the console 63 by selecting the desired direction of the cleaninf unit, and in turn, actuates the valve 43 to obtain the desired direction of flow. The hydraulic fluid also passes through line 49 to steering ram 34 or 35 via the valve 44. Actuation of the valve 44 is controlled by a suitable steering mechanism (not shown) at the console 63 and the amounts of fluid allowed to pass through line or 51 determines the selected movement of either piston 36 or 37 respectively, and hence the direction of rotation of sprocket wheel 32, particular reference being made to FIG. 7. Fluid may pass between the rams 34 and 35 through the common line 470. In operation (with reference to FIG. 8) the valve 44 may be actuated by solenoids 44a (see FIG. Se), in which case the fluid flows through line 50, thereby causing the piston 36 to go from left to right. This, in turn, allows fluid to flow through the common line 47a and into steering ram 35. As shown in FIG. 7, the two rams are connected to the sprocket 32 by means of a chain 38 and thus if the piston 36 moves from left to right, piston 37 will move from right to left and thus, fluid is forced through line 51 to line 48a via valve 44, causing the yoke 31 (see FIG. 6a) by means of the sprocket wheel 32 to be rotated in one direction. Likewise, the reverse direction of rotation is obtained when solenoid 44b is actuated (see FIG. 8f) and fluid flows into line 51. Valve 47 functions as a drainage seal should there be any leakage from the rams. Thus, it is appreciated that by virtue of the inter-connecting line 47a, the pistons 36 and 37 operate in a highly desirable manner. A relief valve 41 is provided conveniently operating at a pressure of 1,000 psi or more so that excess pressure is not built up in the hydraulic system.

In the preferred embodiment of the invention the peripheral edge of the chamber which bounds the open side 12 and which comes into close proximity with the submerged surface is provided with a series of corrigations 26 therein. See FIG. 9. In this manner turbulent conditions are established, and the ingress of water is reduced. This means that less power is required in maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber in order to hold the unit against the submerged surface. The use of these corrugations at the edge of the chamber 1 bounding the open side thereof is not only applicable to the maneuverable form of apparatus (with or without one or more cleaning devices) described heretofore, but is also applicable to repair and/or maintenance caissons, e.g., working over a substantially flat man-made surface whence it is lowered into position by means of cables or wires. According to this embodiment of the invention, there is provided, an apparatus suitable for attaching to a submerged surface comprising a chamber having an open side, a pressure reducing device capable of continuously maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber, and a series of corrugations in the edge of the chamber which bounds the open side and which edge comes into close proximity with the submerged surface.

Such an apparatus may be operated by allowing the apparatus to enter the water near the hull of a ship to a suitable depth, and activating the pressure reducing device whereby the chamber attaches itself to the hull. The corrugations 26 used in this invention are preferably continuous, and preferably define an area of the same shape as the open space bounded by this edge. Thus, if the open side is circular or oval in shape, the currugations enclosure circular or oval areas also. The corrugations, however, may be discontinuous and inclined at an angle to the bounding line of the open side, e.g., with a circular open side, there could be a series of corrugations forming non-intersecting tangents with the inner boundary of the open side. The profile of the corrugations may vary considerably. They may, for example, be symmetrical or unsymmetrical, e.g., sinusoidal, circular, square, V-shaped or of other profiles with sharp edges.

Preferably the corrugations are arranged so that in proceeding from the outside to the inside of the chamber across the edge bounding the open side one transverse at least two corrugations, and more preferably six corrugations or more. In the preferred case the open side is circular in shape and the edge of the chamber has six corrugations therein, the profile preferably being sinusoidal.

The use of corrugations at the edge of the chamber is shown in FIGS. 4 and 6 of the drawings, and they are shown in greater detail in FIG. 9 of the drawings which shows an enlarged side view of the chamber. in FIG. 9

six. corrugations are shown .at 26, which are substan of the orderof about 2,5 cm. v

In other forms of the invention the' apparatus (with or without one or more cleaningdeViceS) may include conventional devices for indicating the attitude of the indicating the attitude of the steerable wheel 4, respectively. The rotatable drum 55 is-controlledby the device for sensing the position of the chamber relative to steerable wheel 4 and the chamber (e.g., standardgravity-controlled pendulum and 'magsliparrange-f ment), and a device for sensing the position of the chamber relative to said submerged surface (e.g., standard hydrostatic pressure responsive gauge).

Preferably the attitude of the chamber and the steerable wheel are visibly indicated on the screen of the console 63 by means of suitable representations (e.g., small replicas). The console screen is, preferably marked with graduated parallel lines so that the posi tion of the chamber is indicated by movement of the screen which is controllable by the device which senses the position of the chamber. With this information an operator can readily ascertain the position and attitude of the chamber, and the attitude of the steerable wheel, and take any necessary corrective measures to keep the maneuverable chamber on its desired course. The depth of the cleaning unit is detected by means of the pressure transducer schematically represented at 21 and mounted on the unit. This transducer will provide a signal to the console which provides a suitable visible indication of depth. As described in further detail hereafter the monitor comprises a vertically moving surface graduated in horizontal lines which correspond to depth (feet). A typical arrangement may have been connected to the moving surface a takeup drum (not shown) at the top and bottom with the drive being applied by means of a conventional capacitor motor through a belt-driven pulley and gears, and a chain link between the top and bottom drums. As the chamber 1 increases the depth, the depth indicator responds ac cordingly by sending an appropriate signal to the motor which causes the surface 55 to move, thereby registering the corresponding depth at the console 63 to provide the operator with an indication of th depth of the unit.

One method of operating the preferred embodiment of this invention comprises allowing the apparatus to enter the water near the hull of a ship to a suitable depth, activating the pressure reducing device whereby the chamber attaches itself to the hull, operating the driving motor whereby the apparatus moves over the surface of the hull, noting the attitude and position of the chamber and the attitude of the steerable wheel, and controlling the course of the chamber using the information which has been sensed from the apparatus and displayed at the console. If it is desired to clean the sides of the ship, the brush motors are activated before or when the chamber has attached itself to the hull. To remove the apparatus from the water, the activation of the pressure reducing device is stopped, and the apparatus is recovered, e.g., by allowing it first to float to the surface, or by raising it by means of cables or wires attached to the apparatus.

Referring to F l0. 10, the rotatable drum 55 has parallel graduated lines 56. In front of this drum is pivoted about 57 a replica of the chamber 58. About a pivot 59 attached to the replica 58 is pivoted another replica 60, this being a replica of the steerable wheel 4. These two replicas 58 and 60 are controlled by the device for indicating the attitude of the chamber and the device for the submerged surface, whicli1 in this case isia system capable of generating an inductive signal in proportion to the deflection ,of an evacuated capsule under changing hydrostatic pressure. i t

Full controlof the apparatus is achieved by the operator observing the position of the replicas 58 and 60 and of the position of the drum 55 as indicated by the parallel lines 56, and taking any correcting measures necessary to keep the apparatus on its desired course.

Although the present invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example and that obviously changes in the details of constuction and arrangement of parts may be resorted to without departing from the spirit and scope of the invention. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.

Having thus set forth the nature of the invention, what is claimed herein is:

1. An apparatus capable of being driven along a submerged surface and cleaning said surface, comprising a chamber having an open side, supporting means for maintaining the open side of said chamber at a distance from said surface, said supporting means including wheel means, driving means connected to said wheel means for causing said chamber to move along said surface, pressure reducing means operably connected with said chamber for continuously maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber, steering means mounted with said chamber for directionally moving said apparatus as it is driven along the submerged surface, said wheel means further including a wheel operably connected with said steering means and capable of being swivelled through an angle of at least and cleaning means comprising brush means mounted for rotation about an axis substantially perpendicular to the surface to be cleaned, means to rotate said brush means so that when said brush means are compressed against said surface the bristles thereon rotate in a plane substantially parallel to said surface.

2. An apparatus as claimed in claim 1 wherein said wheel is free to swivel through 360.

3. An apparatus as claimed in claim 1 wherein the steering means comprises hydraulically operated steering rams.

4. An apparatus as claimed in claim 1 including a series of corrugations disposed about the edge of the chamber which bounds the open side and which edge is disposed in close proximity to the submerged surface.

5. An apparatus as claimed in claim 4 wherein the corrugations are continuous.

6. An apparatus as claimed in claim 5 wherein the open side is circular, the corrugations enclose a circular area, and the profile of the corrugations is sinusoidal.

7. An apparatus capable of being driven along a submerged surface and cleaning said surface, comprising a chamber having an open side, said chamber including a series of corrugations disposed about the edge of said chamber which bounds said open side and facing said submerged surface, supporting means for maintaining the open side of said chamber at a distance from said nected with said steering rams and capable of being swivelled through an angle of at least and cleaning means comprising brush means for rotation about an axis substantially perpendicular to the surface to be cleaned, means to rotate said brush so that when said brush means are compressed against said surface the bristles thereon rotate in a plane substantially parallel to said surface. 

1. An apparatus capable of being driven along a submerged surface and cleaning said surface, comprising a chamber having an open side, supporting means for maintaining the open side of said chamber at a distance from said surface, said supporting means including wheel means, driving means connected to said wheel means for causing said chamber to move along said surface, pressure reducing means operably connected with said chamber for continuously maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber, steering means mounted with said chamber for directionally moving said apparatus as it is driven along the submerged surface, said wheel means further including a wheel operably connected with said steering means and capable of being swivelled through an angle of at least 90*, and cleaning means comprising brush means mounted for rotation about an axis substantially perpendicular to the surface to be cleaned, means to rotate said brush means so that when said brush means are compressed against said surface the bristles thereon rotate in a plane substantially parallel to said surface.
 2. An apparatus as claimed in claim 1 wherein said wheel is free to swivel through 360*.
 3. An apparatus as claimed in claim 1 wherein the steering means comprises hydraulically operated steering rams.
 4. An apparatus as claimed in claim 1 including a series of corrugations disposed about the edge of the chamber which bounds the open side and which edge is disposed in close proximity to the submerged surface.
 5. An apparatus as claimed in claim 4 wherein the corrugations are continuous.
 6. An apparatus as claimed in claim 5 wherein the open side is circular, the corrugations enclose a circular area, and the profile of the corrugations is sinusoidal.
 7. An apparatus capable of being driven along a submerged surface and cleaning said surface, comprising a chamber having an open side, said chamber including a series of corrugations disposed about the edge of said chamber which bounds said open side and facing said submerged surface, supporting meanS for maintaining the open side of said chamber at a distance from said surface, said supporting means including wheel means, driving means connected to said wheel means for causing said chamber to move along said surface, pressure reducing means operably connected with said chamber for continuously maintaining a reduced pressure inside the chamber relative to the pressure outside the chamber, steering means including steering rams mounted with said chamber for directionally moving said apparatus as it is driven along the submerged surface, said wheel means further including a wheel operably connected with said steering rams and capable of being swivelled through an angle of at least 90*, and cleaning means comprising brush means for rotation about an axis substantially perpendicular to the surface to be cleaned, means to rotate said brush so that when said brush means are compressed against said surface the bristles thereon rotate in a plane substantially parallel to said surface. 